Type of active transport that helps muscle cells contract is the sodium - potassium pump. This pump involves the process of transferring sodium ions and potassium ions across a cell membrane through active transport type of diffusion. It is a process which needs an input of energy for it to proceed. For this process, it takes it energy fro the hydrolysis of ATP. It makes use of the enzyme Na+/K+-ATPase for this process. This active transport is mainly responsible of the regulation of Na+ outside a cell and K+ ions inside the cell. The unbalanced charge present would contributr to the separation of the charges through the cell membrane.